title: Longitudinal trajectory of vitamin D status from birth to early childhood in the development of food sensitization.
abstract: BACKGROUND
  Increasing evidence supports the immunomodulatory effect of vitamin D on allergic diseases. The combined role of prenatal and postnatal vitamin D status in the development of food sensitization (FS) and food allergy remains understudied.
  
  
  METHODS
  Plasma 25-hydroxyvitamin D (25(OH)D) levels of 460 children in the Boston Birth Cohort (BBC) were measured at birth and early childhood, and the subjects were genotyped for rs2243250 (C-590T) in the IL4 gene. We defined FS as specific IgE levels of ≥0.35 kUA/l to any of eight common food allergens; we defined persistently low vitamin D status as cord blood 25(OH)D <11 ng/ml and postnatal 25(OH)D <30 ng/ml.
  
  
  RESULTS
  We observed a moderate correlation between cord blood 25(OH)D at birth and venous blood 25(OH)D measured at 2-3 y (r = 0.63), but a weak correlation at <1 y (r = 0.28). There was no association between low vitamin D status and FS at any single time point alone. However, in combination, persistence of low vitamin D status at birth and in early childhood increased the risk of FS (odds ratio (OR) = 2.03, 95% confidence interval (CI): 1.02-4.04), particularly among children carrying the C allele of rs2243250 (OR = 3.23, 95% CI: 1.37-7.60).
  
  
  CONCLUSIONS
  Prenatal and early postnatal vitamin D levels, along with individual genetic susceptibility, should be considered in assessing the role of vitamin D in the development of FS and food allergy.
authors.affiliation: Mary Ann and J. Milburn Smith Child Health Research Program, Department of Pediatrics, Northwestern University Feinberg School of Medicine and Ann & Robert H. Lurie Children's Hospital of Chicago Research Center, Chicago, IL, USA. xnliu@luriechildrens.org
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Lester
authors.initials: L
authors.lastname: Arguelles
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhou
authors.forename: Guoying
authors.initials: G
authors.lastname: Wang
authors.forename: Qi
authors.initials: Q
authors.lastname: Chen
authors.forename: Hui-Ju
authors.initials: HJ
authors.lastname: Tsai
authors.forename: Xiumei
authors.initials: X
authors.lastname: Hong
authors.forename: Rong
authors.initials: R
authors.lastname: Liu
authors.forename: Heather E
authors.initials: HE
authors.lastname: Price
authors.forename: Colleen
authors.initials: C
authors.lastname: Pearson
authors.forename: Stephanie
authors.initials: S
authors.lastname: Apollon
authors.forename: Natalie
authors.initials: N
authors.lastname: Cruz
authors.forename: Robert
authors.initials: R
authors.lastname: Schleimer
authors.forename: Craig B
authors.initials: CB
authors.lastname: Langman
authors.forename: Jacqueline A
authors.initials: JA
authors.lastname: Pongracic
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Wang
mesh_terms: D001900:Boston; D002675:Child, Preschool; D015331:Cohort Studies; D005312:Fetal Blood / Q000737:chemistry; D005333:Fetus; D005512:Food Hypersensitivity / Q000209:etiology* / Q000276:immunology; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007223:Infant; D007231:Infant, Newborn; D015847:Interleukin-4 / Q000235:genetics*; D016015:Logistic Models; D008137:Longitudinal Studies; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; D015847:Interleukin-4; D007073:Immunoglobulin E; C104450:25-hydroxyvitamin D